Free Journeyman Electrician's Basic Formula Questions and Answers

Question 1

What does the letter "E" stand for in the PIE formula circle?

Accepted Answer

Voltage

Answer

Power

Answer

Current

Answer

Resistance

Question 2

The current in a single-phase circuit is defined by which formula?

Accepted Answer

I = P/E

Answer

I = E/P

Answer

I = V x A

Answer

I = P x E

Question 3

What is the highest value that the power factor can possibly be?

Accepted Answer

100%

Answer

50%

Answer

200%

Answer

There is no limit for the value of power factor

Question 4

When will the voltage and the current both peak and reach zero simultaneously?

Accepted Answer

When they are in-phase

Answer

When the circuit contains capacitance

Answer

When the circuit contains inductance

Answer

When they are out-of-phase

Question 5

Given that the electrical load has a power factor of 0.8 and a voltage of 240 volts, determine its current.

Accepted Answer

1.56 amperes

Answer

1 ampere

Answer

0.8 amperes

Answer

1.25 amperes

Question 6

Find the voltage drop of two copper wires of size 10 AWG that are 100 feet away from the voltage source and are powering an 8-amp load. Given: The two conductors' combined resistance is 0.2 ohms.

Accepted Answer

1.6 volts

Answer

8 volts

Answer

80 volts

Answer

16 volts

Question 7

Six horsepower equals:

Accepted Answer

4,476 watts

Answer

746 watts

Answer

2.4 kilowatts

Answer

4 kilowatts

Question 8

How many amperes of current, in terms of watts, can a microwave oven rated at 1,200 watts draw?

Accepted Answer

10 amperes

Answer

15 amperes

Answer

5 amperes

Answer

0.1 amperes

Question 9

Calculate the power factor of a 5 kW load using a 208 volt, single phase source to draw 30 amperes of current.

Accepted Answer

80%

Answer

46%

Answer

83%

Answer

92%

Question 10

When a 480 Y/277 volt, three-phase, 4-wire electrical system is used to supply a commercial service with a 400 ampere rating, the service is rated as follows:

Accepted Answer

332.5 kVA

Answer

110.8 kVA

Answer

144.1 kVA

Answer

192 kVA